Achieving Significant Nail Clearing After 13 Years Of Failed Treatment For Thick, Discolored Toenails

This author discusses the use of a topical compound to treat a patient who endured years of failed topicals and multiple debridements for thick, diseased toenails. 

Not all thick toenails are fungal. There is a misperception that thick toenails are always onychomycosis. Onychomycosis is a common toenail infection caused by dermatophytes, non-dermatophytes and mold that can worsen and become painful if left untreated. Onychomycosis reportedly occurs in 10 percent of the general population, 20 percent of people older than 60 years of age and 50 percent of those older than 70 years of age.¹

The most sensitive test for fungus of nail specimens is the periodic acid-Schiff test (PAS).² However, with the multiple negative test results on obvious diseased nails I was receiving in my office, I ran a series of DNA tests in 2015 on 16 thick toenail clippings. Only one culture result was purely fungal. Four test results came back with a fungal species identified in addition to various mixed bacterial species being detected. The other 12 nail cultures had multiple bacterial species without a fungal component. The common antifungal treatments available including oral medications, topical agents and laser therapy would then, in theory, only effectively treat one of the 16 toenails that I tested.

While every aforementioned nail specimen yielded some diagnostic results, it is important to keep in mind that negative PAS tests can be a misnomer of a lack of pathology to a nail. This can lead to a lack of treatment or improper treatment of thick toenails with multiple failed treatments leaving the patient and physician frustrated.

In February 2005, a 62-year-old female patient saw a previous podiatrist for thick toenails causing pain in her shoes with walking. She was treated with oral terbinafine (Lamisil, Novartis Pharmaceuticals) and topical ciclopirox nail solution. The patient followed up in 2006 and 2007 with the same doctor requesting a refill of her topical prescription even though her toenails were not showing improvement.

The patient then presented as a new patient in my office in 2011 with the continued complaint of thick, discolored, painful toenails. A subsequent PAS test revealed Candida parapsilosis. After discussing available options, the patient used the topical combination of tolnaftate and jojoba oil (Formula 3, Tetra Corporation),tavaborole (Kerydin, PharmaDerm) topical nail solution, another course of oral terbinafine and multiple debridements over seven years with failure to improve.  

In December 2017, I had the patient start using a topical nail compound of amphotericin B 3%, terbinafine 1%, thymol 1% and urea 20% in a Recura™(Humco) base cream. The patient followed up in the office two months later with three mm of proximal nail clearing noted for the first time in 13 years (see Figure 1). I saw the patient for two additional appointments for nail debridement and evaluationand as of November 2018, she is 90 percent cleared of her diseased nails (see Figure 2).

In my opinion, there were two main reasons for the efficacy of this new topical formulation. First, as I have documented above, most perceived nail fungus cases are rarely caused by dermatophytes alone. With the formulation in question, the amphotericin B covers dermatophytes and non-dermatophytes, terbinafine covers dermatophytes, and thymol covers dermatophytes and bacteria. Therefore, regardless of the microorganism responsible, this option should provide adequate treatment. 

Secondly, the Recura base has demonstrated nail plate penetration in three different in-vitro models, which helps ensure the active ingredients reach the infected area.³ Furthermore, the base of the topical compound contains tea tree oil and 20% urea to help soften the nail and increase porosity.

After seeing these results, I have started multiple patients in my office on this newer topical nail compound with noted proximal nail clearing in 100 percent of patients at follow-up appointments.

In my experience, the key to treating thick toenails is to understand that fungus is not always the main species, hence why “nothing” works. The discussed topical nail formula has proven invaluable to effectively treat thick diseased toenails in my practice. Utilizing more sensitive testing options and addressing all microorganisms causing pathology of the nail are imperative in achieving overall success with thick, diseased toenails.

Dr. Benjamin is in private practice in Littleton, Colo., and is a former member of the Colorado Board of Podiatry. 

1. Westerberg DP, Voyack MJ. Onychomycosis: current trends in diagnosis and treatment. Am Fam Physician. 2013:88(11):762-770.
2. Blake N, Zhu J, Hernandez G, Juliano PJ. A retrospective review of diagnostic testing for onychomycosis of the foot. J Am Podiatr Med Assoc. 2015:105(6):503-508.
3. Christensen L, Turner R, Weaver S, et al. Evaluation of the ability of a novel miconazole formulation to penetrate nail by using three in vitronail models. Antimicrob Agents Chemother. 2017;61(7). doi: 10.1128/AAC.02554-16.